There does indeed seem to be a certain limit to what the PMUs which are an official part of the Iraqi military and Iranian forces are willing to take before more severe responses, possibility leading to full-blown open warfare, are decided upon. For Iran that red line is quite open and crystal clear; if Iranian soil is attacked by America then it's gloves off. During the attack on Ayn Al-Assad, several more waves of missiles (ranging in the hundreds of BMs) were already prepared and ready to go if the U.S. military were to retaliate against Iranian assets on Iranian soil (guess what didn't happen?). To me and many others this is a sign that Iran has overtly accepted, like I elucidated before, its willingness to take whatever losses in order to protect the Iranian homeland. To make myself even more clear, and further delineate upon what it is I'm trying to get across to you. Iran most likely can't win an open conflict with American forces if the war lasts for too long, Iran knows that, we know that but they've prepared to engage the U.S. in ways that they can sustain a conflict in. Iran can really hurt American standing in the Middle East if a high-intensity short-duration conflict is initiated but if that drags out Iran will really be feeling the hurt. The United States simply has the bigger economy and pool of resources to use in long form factor engagement, coupled with the larger military, this will lead to a "victory" of some sort. Although that aim is seriously in question since Iran really isn't alone here, it has allies/proxies that have been well equipped and armed can/will create a big problem for the U.S. the region over if they decide to get involved (high likely-hood). That's neither here nor there though....You seem to be insinuating that Iran is afraid of the U.S. and the attack on Ayn Al-Assad was just some hollow face-saving attempt to get back at the U.S. for killing a well respected General. Fair enough, that is your stance, I don't think that is what went down but I respectively have a different perspective on it